Various 99m Technetium labeled phosphate compounds have been tested for their use as bone imaging agents using a variety of radiographic bone scanning techniques. In general, the prior art methods prepared bone imaging agents by mixing a solution of Technetium-99m as the pertechnate with a freeze-dried mixture of a phosphate or a phosphonate compound and stannous chloride employed as the reducing or complexing agent. These prior art methods are referred to in detail in RADIOPHARMACEUTICALS, edited by Subramanian, Rhodes, Cooper, and Sodd, 1975, particularly in the chapter entitled, "An Evaluation of 99m TC Labeled Phosphate Compounds as Bone Imaging Agents" pp. 319-328 inclusive. This reference indicates that 99m TC labeled methylene diphosphonate is the agent of choice for bone imaging in nuclear medicine.
More recently, additional phosphonate compounds have been tested as both skeletal and myocardial infarct agents--JOURNAL OF NUCLEAR MEDICINE, June 1975, p. 540. Here there is described the use of various ethylene diamine polyphosphonic acid and, in particular, diethylene triamine penta (methylene phosphonic acid). The particular phosphonates mentioned are reported to be likely candidates for clinical use in view of the fact that they are cleared from the blood more rapidly than the agents utilized in the past.